Method and apparatus for handling slag



Feb. 18, 1936. R. N, WILSON METHOD AND A PPARATUS FQR HANDLING SLAG 2 Sheets-Sheet 1 Filed June 11, 1932 EA/NO/V) IV- W N Gttornegs Feb. 18,- 1936. R. N. WILSON METHOD AND APPARATUS FOR HANDLING SLAG Filed June 11, 1932 2 Sheets-Sheet 2 Snnentor RA YNO/VD /V- W 50/1/ (IttornegS Patented Feb. 18, 1936 UNITED STATES- METHOD AND APPARATUS FOR HANDLING SLAG Raymond N. Wilson, Cleveland, Ohio Application June 11, 1932, Serial No. 616,637

'3 Claims.

This invention relates to an improved method of handling blast furnace slag and pertains further to apparatus adapted for use in conjunction with the practice of such method.

' In the operation of blast furnaces for the production and manufacture of ferrous metal, each time the furnace is tapped to draw off the molten metal a quantity of slag, formed during the heat, must be discharged and disposed of before a subm sequent withdrawal of metal can be made. It has been customary to draw the slag from the furnace in a molten condition conveying the same in cars or ladles to some remote point where it is poured to cool and solidify. Frequently, in

such practice, the slag becomes chilled before it reaches the slag dump and large molten blocks or skulls are formed which subsequently have to be re-conveyed in cars or bysimilar vehicular means to a crusher where the slag is broken and prepared for commercial uses. This method entails the use of large area of property and costly handling equipment as the material must be hauled to the slag dump where it is stored until the capacity of the crusher mill warrants its transfer thereto. As the material at this stage consists of molten blocks and stratified layers of fused material, steam shovels or similar equipment must be employed to load the cars that convey the material to the crushers. At the crusher mill the slag is again loaded upon cars and hauled to a second storage area from which the commercial product is drawn as it is-sold.

It is the object of the present invention to provide an improved apparatus which will obviate the arduous labor, handling costs and equipment investment attendant the foregoing practice and further to provide apparatus which will prepare the slag for commercial uses in a more economical and expeditious manner.

Another object of the invention is to provide mechanism for handling slag which will effectuate the production of a commercial product of a superior quality, that is, slag consisting of granules of uniform size and of a hard firm texture.

Other objects more or less ancillary of the foregoing and the manner in which all the varipus objects are realized will appear in the following description which, considered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention.

Referring to the dr-awings- Figure 1 is an elevational view, partially in section, of a fragmentary portion of a blast furnace and illustrating the improved apparatus for handling slag constituting the present invention.

Figure 2 is an elevation of a portion of the slag handling apparatus as viewed at a right angle to the illustration shown in Figure 1.

Figure 3 is a detailed View, partially in section, illustrating the mechanism used in conveying slag from the furnace and the structure of the hopper embodied in the present invention.

Referring to the blast furnace ll) illustrated in Figure 1 the structure shown therein comprises the conventional type of furnace save that a sump or trough M is provided in the furnace adjacent the base portion thereof. The walls of this trough are preferably formed to converge in a common plane so as to effect the drainage of the molten slag remaining in the furnace after the metal has been discharged. At the base of the trough ll there is a canal 12 which is disposed to permit the molten slag to flow into buckets !3 arranged upon a continuous link belt I4. The conveyor belt is mounted upon sprockets it: carried by a shaft suitably journaled in bearings anchored in the walls of the furnace and also upon sprockets 56 mounted near the top of a tower I? which is situated a short distance from the blast furnace. The sprockets may be driven by any suitable source of power, the rate of rotation thereof depending upon the allocation of the tower with respect to the furnace and upon the size of the orifice in the canal l2 which controls the flow of the molten slag to the con.-

veyor buckets !3. Intermediate the tower 'l l and the base of the blast furnace there is a tressel 18 provided to support and guide the conveyor belt and further to accommodate a canopy or roof I9 having shutters or adjust-able louvers 20 therein to control the dissipation of heat from the slag during the translation thereof over the tressel H5.

The tower ll preferably comprises a rectangular structural frame work having a hopper or chute 2| disposed therein. At the mouth of the chute 2| there is a grating 22 which is formed with a plurality of spaced rails 23, the faces thereof being suitably configured to eflect the division of the cooled slag which falls thereon when the buckets I3 are inverted by revolving over the sprockets l6.

Adjacent the upper sprockets there is a buffer plate 24 which is arranged to engage rollers upon the forward face of the buckets I3 during their rotation over the sprockets. The buffer plate is pivotally mounted upon brackets 25 supported on the tower frame and is yieldingly supported through contractile springs 26. As the buckets l3 pass over the buffer 24 the roller upon the forward edge of the buckets will engage the face of the buffer and compress the springs 26. Upon the disengagement of the roller the buffer will fly outwardly under the influence of the springs 26 and strike the forward edge of the next succeeding bucket, thus effecting a blow of suiiicient impact to dislodge the contents of the buckets.

As illustrated in Figures 1 and 2 the tower I1 is constructed of suitable height and width to permit a railway car 21 to be drawn under the hopper to thus facilitate the ready loading thereof.

In operation after the molten metal is discharged from the furnace the slag may be drawn therefrom through the canal l2 by opening a gateway 28 which may be of any suitable construction. As the molten slag flows from the sump in the furnace ll it will fill the conveyor buckets l3 and be elevated to the top of the tower I! by the conveyor belt I 4. The height of the tower and the lateral location thereof may be organized to accommodate a period of travel sufficient for the molten slag to become partially cooled. Moreover, the rate at which the conveyor belt is driven, the discharge rate from the furnace and the shutter control in the canopy I!) may all be manipulated to further effect the desired thermal control over the slag during its translation to the top of the tower I IV In some commercial uses slag of extremely porous and brittle character has been found objectionable. The grain and porosity of such material is caused by the deleterious action of water upon the slag before it was sufficiently cooled. In the present invention exposure to moisture is avoided by the provision of the canopy l 9 which enshrouds the conveyor chain throughout its exposed length thus aifording a means of control of the heated material throughout the entire cycle of operation.

A further advantage in handling the material with the apparatus heretofore described resides in the accessibility of iron recovery from the slag before it reaches the crusher mill. As the buckets contemplated for use herein are shallow the material will be cooled in a relatively short time and the iron remaining in the slag will settle in the bottom of the buckets and will be likewise cooled before the buckets are inverted and discharged. When the material falls upon the grating it will be disrupted and may be then further cooled so that electromagnets may be employed to separate and accumulate the fragments of ferrous material before it reaches the cars which convey the slag to the crushers. I

It will be readily seen from the foregoing that the wide areas of property used for storage purposes may be eliminated and that the cost of operation and maintenance may be minimized by the application of the apparatus and by the practice of the method of handling and treating slag as here defined.

Although the foregoing description is necessarily of a detailed character, in order that the invention may be completely set forth, it is to be understood that the specific terminology is not intended to be restrictive or confining, and that various rearrangements of parts and modifications of structural detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.

I claim:

1. In combination with a blast furnace having an outlet passage in the base portion thereof, a tower in juxtaposition with said furnace, a structure uniting the top of the tower with the base portion of said furnace and associated with said outlet passage thereof, a conveyor belt within said structure, buckets mounted upon said conveyor belt, arranged to receive molten slag discharged from said outlet passage and deposit same in a solid condition at the top of said tower, a roof upon said structure, means within said roof to facilitate the control of the dissipation of heat from the slag and a grating adjacent the base of the tower to effect the disruption of the slag by its fall thereon.

2. In combination with a blast furnace having wall portions formed to constitute a sump at the base thereof adapted to receive and temporarily retain molten material from the furnace, an outlet passage communicating with the sump, means for controlling the flow of material from the sump, a tower located adjacent the furnace, an inclined conveyor having its receiving extremity located adjacent the outlet of the sump and its discharge extremity located at the top of the tower, said conveyor being provided with a series of pivotally mounted buckets arranged to receive the molten material discharged from the sump and convey it to the top of the tower, the material while being conveyed attaining a solidified state, means for controlling the rate of solidification While being conveyed, means located adjacent the top of the tower for effecting discharge of the material from the buckets, a hopper arranged to receive the discharged material, and a grating located at the bottom of the hopper for disrupting the material falling thereon.

3. In combination with a blast furnace having wall portions formed to constitute a sump at the base thereof adapted to receive and temporarily retain molten material from the furnace, an outlet passage communicating with the sump, means for controlling the flow of material from the sump, a tower located adjacent the furnace, an inclined conveyor having its receiving extremity located adjacent the outlet of the sump and its discharge extremity located at the top of the tower, said conveyor being provided with a series of relatively shallow pivotally mounted buckets arranged to receive the molten material discharged from the sump and convey it to the top of the tower, the material while being conveyed attaining a solidified state, a cover for said conveyor to protect the slag from the deleterious action of water while cooling, means associated with said cover for controlling the rate of cooling of the slag, means located adjacent the top of the tower for effecting discharge of the material from the buckets, a hopper arranged to receive the discharged material, and a grating located at the bottom of the hopper for disintegrating the material falling thereon.

RAYMOND N. WILSON. 

